“Not enough shut-eye puts your body into a carb- and fat-craving survival mode,” says Michael Breus, PhD, author of The Sleep Doctor’s Diet Plan. A study in The American Journal of Clinical Nutrition found that women who slept fewer than four hours ate 300 more calories and 21 more grams of fat the next day.
Try this to gauge your sleep needs: For a week, go to bed seven and a half hours before you need to get up. If you awaken before the alarm, you can get by with less sleep. But if you hit snooze, you may need eight, even nine, hours a night to wake up refreshed, recharged, and ready to burn some fat.
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